The 25-year-old has slipped down the pecking order at Goodison Park so far this season, failing to make a single Premier League start and appearing just six times across all competitions for the Toffees.

The Bosnia-Herzegovina international has now dropped down to the Championship in search of more regular first-team football, joining Boro until the end of the campaign.

Besic's deal went through shortly before the 11pm transfer deadline, and the holding midfielder could now make his debut for the club away to Norwich City on Saturday.